Multiple clutch mechanism



June 2, 1942. B. F. MADSEN MULTIPLE CLUTCH MECHANISM Original Filed April 20, 1938 FIG.

illlll i .FIG. 4

FIG. 3

INVENTOR. BERTHEL F. MYADSEN A ORNEY.

Patented June 2, 1942 UNITED MULTIPLE CLUTCH DIECHANISM Barthel F. Madsen, Chicago, 111., assignor to Teletype Corporation, Chicago, 111., a corporation of Delaware Original application April 20, 1938, Serial No.

Divided and this application December 26, 1939, Serial No. 310,938

11 Claims.

This invention relates to printing telegraph apparatus and particularly to clutch mechanisms through which power is transmitted for performing various operations in the printing telegraph apparatus.

This application is a division of copending application Serial No. 203,021, filed April 20, 1938, by Berthel F. Madsen.

An object of the invention is to divide the performance of functional operations in a printing telegraph apparatus between two cam as sembliessupported by a single driving shaft but itndependently driven thereby in overlap relaion.

The invention features an arrangement for driving the operating cams of a printing telegraph receiving unit in which there is a plurality of cam assemblies carried by a driving shaft, one of the cam assemblies including cams for performing certain operations, and in addition a cam for controlling a pawl and ratchet combination through which rotation is imparted by the driving shaft to the other cam assembly. In the copending application of Berthel F. Madsen above identified and also in Patent No. 2,247,408

to Albert H. Reiber there is disclosed a type wheel printer in which the present invention is adapted to be employed. According to the disclosures of the above-identified application and patent the type wheel is slidably mounted upon the type wheel shaft and is supported by a shiftable frame, the normal position of which is such that the entire type wheel is held below the level at which printing is to be effected so that a line which is being printed, including the last character, shall be visible. For each cycle of operation of these receiving units the type wheel supporting frame is oscillated so as to bring the type wheel into printing position before the printing operation occurs and to restore it to normal position after the printing of the character has been accomplished. The type wheel supporting frame is moved by a cam to bring the type wheel into printing position before the printing operation and is restored to normal position under the control of a cam. The cam which elevates the type wheel to printing position imparts sufficient motion to bring the type wheel above the uppermost of its printing positions. A plurality of stop elements are provided, one for arresting the type wheel in each of the elevational positions from which it may be desired to effect printing. The several stop elements are rendered effective alternatively by the shift and unshift function mechanism of the receiving units, so that these function mechanisms, in stead of shifting the type wheel to the desired position as has been the custom in some kinds of printing telegraph apparatus, merely operate to arrest the type wheel in the desired position. The type wheel elevating mechanism includes a yield instrumentality, so that the type wheel may be arrested short of the uppermost position while permitting the elevating cam and part of the elevating mechanism to operate as if imparting full movement to the type wheel.

In the patent to Albert H. Reiber the cam which elevates the type wheel supporting frame is included in a cam assembly which is carried by a power driven shaft and to which rotation is imparted from the shaft through a clutch mechanism, and the cam which controls the lowering of the type wheel supporting shaft following printing is included in a cam assembly which is carried b a separate and distinctpower driven shaft and to which rotation is imparted from the shaft through a separate and distinct clutch mechanism.

According to the present invention both of the cam assemblies namely, the one which includes the cam for elevating the type wheel supporting frame and the one which includes the cam for controlling the lowering of the frame have been mounted on one power driven shaft to receive rotation independently from that shaft. Individual positive clutch mechanisms are provided for connecting the two cam assemblies to the supporting shaft individually. The clutch through which rotation is imparted to the cam assembly which includes the cam for elevating the type wheel supporting frame is tripped in timed relation to the operation of the signal receiving mechanism of the printing telegraph apparatus. The clutch through which rotation is imparted to the other cam assembly is tripped in timed relation to the operation of the first cam assembly and may, if desired, be tripped by that cam assembly.

For a complete understandingof the invention reference may be had to the following detailed description to be interpreted in the light of the accompanying drawing, wherein Fig. l is a perspective view of the preferred embodiment of the invention wherein two operating cam assemblies are carried by a single driving shaft and are independently driven therefrom, affording the possibilit of nearly a full cyclic interval of lag of one cam assembly behind the other cam assembly;

Fig. 2 is an elevational view partly in section of the apparatus shown in Fig. 1;

Fig. 3 is a plan view of the mechanism shown in Figs. 1 and 2;

Fig. 4 is an elevational view partly in section of an alternative arrangement of operating cam assemblies wherein two cam assemblies are carried by a single driving shaft and are independently driven therefrom, the arrangement affording only a fractional cyclic lag one cam assembly behind the other cam assembly; and

Fig. is a plan view of the apparatus shown in Fig. 4.

Referring to Figs. 1, 2, and 3 the reference numeral II designates a continuously driven shaft which has secured thereto the driving element I2 of a positive drive clutch mechanism, the driven element of which, indicated I3, is slidable axially of shaft II. Driven element I3 is urged by compression spring I4 into engagement with driving element I 2 and is normally held disengaged from driving element I2 by clutch throwout lever I6 which engages the upwardly projecting cam portion I5 of a flange 28 integral with driven clutch element I3. Flange 2!}, with the exception of cam portion I5, is clear of and entirely below the end of clutch throwout lever I6 even when the clutch elements are engaged, so that spring which biases the lever I8 counterclockwise, as viewed in Figs. 1 and 3, may restore the free end of lever I6 to engagement with the peripheral surface of driven clutch element I3 after the tripping of lever I6. However, cam portion I5 of flange 2U revolves in the path of the free end of lever I6, and when it encounters the end of the lever, the driven element I3 is moved downwardly due to the upwardly sloping cam contour, thus moving driven element I3 axially away from driving element I2. Clutch throwout lever'IEi may be arranged to be tripped by any desired timing means such as the selector cam assembly of a printing telegraph apparatus, whereby the tripping of the clutch comprising elements I 2 and I3 may be timed to the reception of signals. Driven clutch element I3 is keyed to a cam assembly sleeve I! which may have secured thereto the cam for elevating the type wheel supporting frame shown in the hereinbefore identified copending application and the sleeve I? may include other function performing cams as desired, as will presently be set forth.

For the sake of simplicity in the drawing such cams have been excluded from the showing of Figs. 1 and 2%. Cam assembly sleeve I? has: secured thereto a cam which is shown in the drawing and is identified I8, the function of which is to set in operation a second cam assembly which will now be described.

Below the cam assembly sleeve I? but having no direct connection therewith, a ratchet I9 is secured to shaft I I. Below the ratchet I9 a disc 2| is supported on shaft II so as to be capable of remaining stationary while shaft I I is rotating. Disc 2| carries a pivoted pawl 22 which is urged by a leaf spring 23 into engagement with ratchet I9. Adjacent to the point at which pawl 22 is pivotally mounted disc 2| is provided with an indentation 24 in the periphery thereof which is of sufficient depth that when pawl 22 engages ratchet IS the tail of pawl 22 swings out over a portion of the indentation. A pawl controlling lever arm 25 is pivotally supported at 2'! and is biased in clockwise direction as viewed in Figs. 1 and 3 by spring 28 which is considerably stronger than leaf spring 23, so that lever arm 26 may threadedly engages cam 3| for adjustably securing the cam to disc 2|. Spring biased bail 34 which may be any element that is to be operated by cam 3| such as, for example, a bail for controlling the lowering of the type wheel supporting frame or a printing bail, supports at its free end a follower roller 36 which engages the periphery of cam 3|.

The retention of cam 3| in rest or idle position is accomplished by the free edge of pawl controlling lever arm 25 which engages the innermost portion of indentation 2 3 in disc 2|, thus serving as a detent for disc 2| and cam 3|, and engaging the tail of pawl 22 to hold it out of engagement with ratchet I9. The clamping screw 33 and slot 32 afford a wide range of adjustment of cam 3| with respect to disc 2| so that the rest position of cam 3| may be varied and the desired relation between cam 3| and its follower roller 36 established. Cam I8, carried by cam assembly sleeve I I, has a portion of sufficient radius, as indicated in dotted lines in Fig. 3, to rock lever arm 26 counterclockwise, whereupon the restraint upon pawl 22 is released and spring 23 rocks it into engagement with ratchet I9. Cam #8 may be positioned on sleeve I I so as to rock lever arm 25 free of pawl 22 at any time during a cycle of rotation of sleeve H, the only limitation being that in its position of arrestment it shall not permit pawl 22 to engage ratchet I 9, whereby cam 3| would be rotated continuously.

As soon as pawl 22 is brought into engagement with a tooth of ratchet I9, which rotates continuously with shaft II, rotation is imparted to disc 2| and therefore to cam 3|. Pawl 22 thus moves out of range of pawl controlling lever arm 26, which in turn is maintained in extreme counterclockwise position by riding against the periphery of disc 2|. During the rotation of cam 3|, cam sleeve I1, controlled by clutch throwout lever It, may remain at rest or may be released for rotation as a result of the reception of another signal combination by the printing telegraph apparatus. As cam 3| completes a cycle of operation the free end of lever arm 26 enters indentation 24 in the periphery of disc 2|, rocks pawl 22 out of engagement with ratchet I9 and, operating as a detent, arrests disc 2| and cam 3|. With this arrangement a plurality of cam assemblies may be carried and driven by a single driving shaft with only slightly less than 360 degres of cyclic lag of cam 3| behind cam assembly sleeve IT, or with any lesser amount of lag. It will be understood that any desired additional cams may be included on the cam assembly sleeve H such as a signal transferring cam and that any desired additional cams may be assembled to the cam 3| and driven therewith such as printing and function performing cams.

The cam driving mechanism shown in Figs. 4 and 5 has some features in common with the mechanism shown in Figs. 1 to 3 inclusive but differs therefrom in that the maximum cyclic lag of one cam assembly behind the other is relatively limited. Reference numeral 4| designates a rotatable shaft to which is secured a driving gear 42. Shaft 4| also has secured thereto the driving element 43 of a positive clutch mechanism which includes a driven element 44 normally restrained from engagement with driving element 43 by clutch throwout lever 46. Compression spring 41 urges driven element 44 to engage driving element 43. Driven element 44 is slidable upon shaft 4| and is keyed to a cam assembly sleeve 48 so that when clutch throwout lever 46 is tripped, cam sleeve 48 and the cams secured to it are released for a cycle of rotation. Below cam sleeve 48 shaft 4| has secured thereto a ratchet 49. Between the ratchet 49 and the gear 42 a cam 5| is rotatably supported on shaft 4| so that it may be held stationary while shaft 4| is rotating. Cam 5| has pivotally mounted thereon a pawl 52 which is biased by spring 53 for clockwise movement into engagement with ratchet 49. Pawl 52 has secured thereto upstanding pin 54 which is of sufiicient height to engage the periphery of a cam 56 carried by cam sleeve 48. Cam 56 performs the same function as cam |8 in Figs. 1 to 3 inclusive; namely, it sets in rotation cam 5| and any desired additional cams that may be associated with cam 5|, as appears by the following description.

In the normal or idle condition of the apparatus shown in Figs. 4 and 5, the clutch comprising elements 43 and 44 is in disengaged condition, cam sleeve 48 is therefore stationary, and in order that cam 51 may also be stationary, pin

54 carried by pawl 52 is engaging the outermost a portion of the periphery of cam 56 whereby pawl 52 is held out of engagement with ratchet 49. Upon the tripping of clutch throwout lever 46, cam sleeve 48 is set in rotation. After rotating through a predetermined angle, cam 55 presents a descending slope to pin 54, whereby pawl 52 is permitted to come into engagement with ratchet 49 and rotation is imparted to cam 5|. Cams 56 and 5| then rotate at the same angular velocity until driven clutch element 44 is disengaged from driving clutch element 43 by clutch throwout lever 49. Upon the arrestment of cam 56, pin 54 carried by pawl 52 is carried forward with respect to cam 56 and ascends the slope which it had previously descended, thus withdrawing pawl when pawl 52 has moved into engagement with ratchet 49, cams 56 and 5| rotate together without relative motion therebetween.

The apparatus shown in Figs. 4 and 5 has particular utility where it is desired to time the performance of an operation such as, for example, the operation of a print bail just after the completion of a cycle of operation of some other function performing cam assembly such as, for example, a cam assembly which includes a transfer cam. As shown in Fig. 5 the bail 51 to be operated by cam 5| may be provided at its free end with a cam follower roller 58 which engages the periphery of cam 5|. Bail 51 may, for example, control printing by overtravel as disclosed in the hereinbefore identified application of Albert H. Reiber, the printing operation occurring as cam follower roller 53 travels down the sharp descent in the periphery of cam 5|. When the overtravel printing mechanism includes a. yield spring as in the embodiment disclosed in the patent to Albert H. Reiber it is not necessary to retract bail 51 immediately from its innermost position with respect to cam 5| and there fore bail 51 may be permitted to serve as a detent for cam 5| to restrain it from responding to any torque which may be imparted to it by shaft 4| due to friction.

Bail 51 may also be employed to increase the cyclic lag between cams 56 and 5 Such increase may be accomplished by timing the apparatus so that the cam 56 shall disengage pawl 52 from ratchet 49 at about the instant that follower roller 58 encounters the top of the descent of cam 5|. The spring biased bail 51 will then impart a torque to cam 5| due to engagement of follower roller 58 with the descending slope, and pin 54 may thus be carried a few additional degrees of angle along the periphery of cam 55. When thereafter cam 56 is set in operation it will rotate through a greater angular distance before pawl 52 engages ratchet 49 than it would had cam 5| been arrested immediately upon disengagement of pawl 52 from ratchet 49.

Although specific embodiments of the features of invention have been disclosed and described herein it will be understood that the invention is not limited to such specific embodiments but is capable of modification, reorganization, rearrangement, and substitution of parts and elements without departing from the spirit of the invention and within the scope of the appended claims.

What is claimed is:

1. In a printing telegraph apparatus, a power driven shaft, a cam assembly member carried by said shaft, means for establishing a driving connection between said shaft and said cam assembly member, a cam assembly carried by said shaft, a ratchet fixed to said shaft, a pawl carried by said cam assembly, means associated with said cam assembly member for conditioning said pawl to become engaged with said ratchet for one revolution of said pawl incident to each revolution of the cam assembly member, and means for engaging said pawl with said ratchet whereby rotation is imparted to said cam assembly.

2. In a printing telegraph apparatus, a power driven shaft, a cam assembly member carried by said shaft, means for establishing a driving connection between said shaft and said cam assembly member, a cam assembly carried by said shaft, means for establishing a driving connection between said shaft and said cam assembly, and means supported by said cam assembly member and said cam assembly for controlling the second mentioned driving connection means.

3. In a printing telegraph apparatus, a power driven shaft, a cam assembly member carried by said shaft, means for establishing a driving connection between said shaft and said cam assembly member, a cam assembly carried by said shaft, means for establishing a driving connection between said shaft and said cam assembly, and means carried by the cam assembly member for controlling the enablement and disablement of the last mentioned means.

4. In a power transmitting device, a power riven shaft, a plurality of elements carried by said shaft to be individually driven thereby, a plurality of clutch mechanisms carried by said shaft for imparting rotation to said elements in dividually, means for initiating engagement of one of said clutch mechanisms, and means associated with the element rotated thereby and operable during its rotation for initiating engagement of the other clutch mechanism for one revolution incident to each revolutionof .the first initiated clutch mechanism.

5. In a power transmitting device, a power driven shaft, a plurality of elements carried by said shaft to be individually driven thereby, a plurality of clutch mechanisms carried by said shaft for imparting rotation to said elements individually, means for initiating engagement of one of said mechanisms, means for controlling the initiation of engagement of the other of said clutch mechanisms and for determining the rest position of the element driven thereby, and means associated with the element rotatedby said one clutch mechanism for actuating the last mentioned means.

6. In a power transmitting device, a power driven shaft, a cam assembly member carried thereby, a spring loaded clutch mechanism for imparting rotation from said shaft to said cam assembly member, a ratchet secured to said shaft, a cam assembly carried by said shaft, a pawl carried by said cam assembly for engagement with said ratchet, means for normally holding said pawl disengaged from said ratchet, means for tripping said spring loaded clutch mechanism to impart rotation to said cam assembly member, and means included in said cam assembly member for disengaging said holding means from said pawl for permitting engagement of said pawl with said ratchet.

7. In a power transmitting device, a power driven shaft, a cam assembly member carried thereby, a spring loaded clutch mechanism for imparting rotation from said shaft to said cam assembly member, a ratchet secured to said shaft,

a cam assembly carried by said shaft, a disc coaxial with and adjusiably secured to cam assembly, a pawl carried by said disc for engagement with said ratchet, means engaging the periphery of said disc for normally holding said pawl disengaged from said ratchet, means for tripping said spring loaded clutch mechanism to impart rotation to said cam assembly member, and means included in said cam assembly member for disengaging said holding means from said pawl for permitting engagement of said pawl with said ratchet.

8. In a power transmitting device, a power driven shaft, a cam assembly member carried thereby, a spring loaded clutch mechanism for imparting rotation from said shaft to said cam assembly member, a ratchet secured to said shaft, a cam assembly carried by said shaft, a disc coaxial with and adjustably secured to said cam assembly having an indentation in theperiphery thereof, a pawl pivotally supported by said disc for engagement with said ratchet, said pawl having an arm extending out over a portion of the indentation in said disc when the pawl is in engagement with the said ratchet, means engaging the periphery of said disc for withdrawing said pawl from engagement with said ratchet upon entrance of the means into said indentation, means for tripping said spring loaded clutch mechanism to impart rotation to said cam assembly member, and means included in said cam assembly member for disengaging said Withdrawing means from said pawl for permitting engagement of said pawl with said ratchet.

9. In a power transmitting device, a power driven shaft, a cam assembly member carried thereby, a clutch mechanism for imparting roiation from said shaft to said cam assembly member, a ratchet secured to said shaft, a cam assembly carried by said shaft, a pawl pivotally supported by said cam assembly for engagement with said ratchet, and means associated with said cam assembly for normally holding said pawl disengaged from said ratchet.

10. In a power transmitting device, a power driven shaft, a cam assembly member carried thereby, a spring loaded clutch mechanism for imparting rotation from said shaft to said cam assembly member, a ratchet secured to said shaft, a cam assembly carried by said shaft, a pawl pivotally supported by said cam assembly for engagement with said ratchet, and means rotatable with said cam assembly member and engaging said pawl for permitting said pawl to engage said ratchet and for subsequently retracting said pawl from engagement with said ratchet.

11. In a power transmitting device, a power driven shaft, a plurality of elements carried by said shaft to be individually driven thereby, a plurality of clutch mechanisms carried by said shaft for imparting rotation to said elements individually, means for controlling engagement of one of said clutch mechanisms, and means associated with the element rotated thereby and operable during its rotation for controlling the actuation of the other clutch mechanism for one revolution incident to each revolution of the first controlled clutch mechanism.

BERTHEL F. MADSEN. 

